A methodological study of the Shipley Institute of Living Scale in alcoholics and non-alcoholics: reliability,...

In Study 1, 430 sober male alcoholics and 98 nonalcoholics completed the Shipley Institute of Living-Vocabulary (SILS-V) and Abstraction (SILS-A) under the standard instructions. Alcoholics performed significantly more poorly than the nonalcoholics on SILS-A. High test-retest reliability of the SILS with a 2-week interval between testings was obtained. Item analysis of the 20-item SILS-A revealed that only items 4-14 discriminated alcoholics and controls, six items required reversal of a cognitive set (reversal) and five did not (nonreversal items). Exploratory factor analyses confirmed essentially the same division of items. In Study 2, two 10-item forms of SILS-A equated for difficulty level and reversal-nonreversal cognitive demands were administered to 186 male and female college students. Results indicate the two forms are equivalent in difficulty, demonstrate no gender differences and correlate significantly with cumulative college grade point averages.